Population Pharmacokinetic Modeling of Pyrazinamide Among Chinese Patients With Drug-Sensitive or Multidrug-Resistant Tuberculosis.

Background: Pyrazinamide is used to treat drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB). This study aimed to characterize the factors associated with the pharmacokinetic parameters of pyrazinamide and evaluate the disposition of the current regimen, which could provide suggestions for adequate dosing strategies for therapeutic targets.

Methods: A population pharmacokinetic model of pyrazinamide was developed based on the data from 499 plasma concentrations from 222 Chinese patients diagnosed with DS or MDR TB. Pyrazinamide exposure was best described using a one-compartment model.

Results: No significant differences were observed in the pharmacokinetic parameters between DS and MDR TB. The final covariate model showed that total body weight was the only significant covariate for apparent clearance, which increased by 0.45 L/h with a 10 kg increase in body weight. A simulation showed that for typical subjects weighing 40-80 kg, a fixed dosage of 1500 mg daily had an area under the concentration-time curve from 0 to 24 hours (AUC0-24) of 389.9-716.0 mg·h/L and peak serum concentrations of the drug (Cmax) of 32.2-44.8 mg/L.

Conclusions: Fixed pyrazinamide doses of 1500, 1750, and 2000 mg are recommended for patients weighing 40-70, 70-80, and 80-90 kg, respectively, to achieve the exposure targets of AUC0-24 > 363 mg·h/L or Cmax > 35 mg/L to attain efficacy.